The Travis County District Attorney's Office announced Wednesday it may have to retest hundreds of DNA results in criminal cases.

The DA's Office said there are scientific concerns over the interpretation of DNA results where multiple contributors might be present.

There is also an “issue related to the database commonly used to calculate DNA statistics.”

Changes to the mixture protocols and database could impact hundreds of cases. However, the exact number of cases that would need to be reviewed is unknown at this time.

The DA's Office is working to identify and address these cases now. The work is expected to be so large, more attorneys and paralegals will be needed at the Conviction Integrity Unit.